Barrier system for the lubricating oil for the bearings of a centrifugal compressor with labyrinth seals installed in a confined environment

A barrier system for lubricating oil for bearings of a centrifugal compressor comprising a compressor having a suction side and delivery side, labyrinth seals defining a compression zone therebetween for at least one impeller, said impeller being mounted on a shaft for rotation at high speed on bearings, a pump which withdraws the lubricating oil for said bearings from a sealed collection vessel and feeds it under pressure through a feed pipe respectively to a first chamber containing one of said bearings and to a second chamber containing another of said bearings, said labyrinth seals, impeller and compression zone being located between said first and second chambers, with said first chamber being on the suction side, and said second chamber being on the delivery side, separate pipes respectively connecting said first and second chambers to a roof of said sealed collection vessel to discharge oil by gravity from said first and second chamber, a disc having an inverted U-shaped rim housing a stator ring rigid with a wall of said first chamber and arranged concentric with said shaft, said disc being concentrically rigid with respect to said shaft, said rotating disc and said stator forming a small passage continuously fed through sized holes in said ring, and kept filled by the centrifugal effect of said rotating disc, with barrier oil bled from a branch pipe of said feed pipe through which lubricating oil is fed under pressure to said first chamber, said stator ring being provided, on a side facing said rotating disc, with a wedge which is inserted into a corresponding cavity in said disc, and with an annular deflector tooth projecting beyond an outer edge of said disc cavity.